Djokovic has been in a funk since completing a career Grand Slam — and a run of four straight major titles — at the French Open in June.

The Serb, who has admitted having “private issues”, lost in Wimbledon’s third round, and then failed to win a match at the Rio Olympics before finishing runner-up at the US Open.

He said he had had a complete change of heart about his approach to tennis because the “must-win mindset… is not working for me any more”.

“I try to be in this moment and take things slowly, and, you know, I’m not rushing anywhere. I’m not in a need, you know, to achieve anything,” he said.

“I feel like I have overcome that step. Right now it’s about just, you know, following my gut, following my instinct, whatever I feel like doing.”

He added: “Just before I arrived to Olympic Games, things were looking great, I was in great shape. I won Toronto. You know, I was, as I can say, the peak of my abilities.

“I was extremely motivated to do well there, but I lost that equilibrium. I lost that balance, because I exaggerated with the way I pushed myself in that kind of preparation and I really, you know, wanted it too much maybe.”